Adding -march=cascadelake to the command line options of the new cmpti2.c
testcase triggers TImode STV and produces vector code that doesn't match
the scalar implementation that this test was intended to check.  Adding
-mno-stv to the options fixes this.  Committed as obvious.

2022-08-07  Roger Sayle  <roger@nextmovesoftware.com>

gcc/testsuite/ChangeLog
	* gcc.target/i386/cmpti2.c: Add -mno-stv to dg-options.

We claim we support P0415R1 (constexpr complex), but e.g.
 #include <complex>

constexpr bool
foo ()
{
  std::complex<double> a (1.0, 2.0);
  a += 3.0;
  a.real (6.0);
  return a.real () == 6.0 && a.imag () == 2.0;
}

static_assert (foo ());

fails with
test.C:12:20: error: non-constant condition for static assertion
   12 | static_assert (foo ());
      |                ~~~~^~
test.C:12:20:   in ‘constexpr’ expansion of ‘foo()’
test.C:8:10:   in ‘constexpr’ expansion of ‘a.std::complex<double>::real(6.0e+0)’
test.C:12:20: error: modification of ‘__real__ a.std::complex<double>::_M_value’ is not a constant expression

The problem is we don't handle REALPART_EXPR and IMAGPART_EXPR
in cxx_eval_store_expression.
The following patch attempts to support it (with a requirement
that those are the outermost expressions, ARRAY_REF/COMPONENT_REF
etc. are just not possible on the result of these, BIT_FIELD_REF
would be theoretically possible if trying to extract some bits
from one part of a complex int, but I don't see how it could appear
in the FE trees.

For these references, the code handles value being COMPLEX_CST,
COMPLEX_EXPR or CONSTRUCTOR_NO_CLEARING empty CONSTRUCTOR (what we use
to represent uninitialized values for C++20 and later) and the
code starts by rewriting it to COMPLEX_EXPR, so that we can freely
adjust the individual parts and later on possibly optimize it back
to COMPLEX_CST if both halves are constant.

2022-08-07  Jakub Jelinek  <jakub@redhat.com>

	PR c++/88174
	* constexpr.cc (cxx_eval_store_expression): Handle REALPART_EXPR
	and IMAGPART_EXPR.  Change ctors from releasing_vec to
	auto_vec<tree *>, adjust all uses.  For !preeval, update ctors
	vector.

	* g++.dg/cpp1y/constexpr-complex1.C: New test.

This patch tweaks i386.md's *cmp<dwi>_doubleword splitter's predicate to
allow general_operand, not just x86_64_hilo_general_operand, to improve
code generation.  As a general rule, i386.md's _doubleword splitters should
be post-reload splitters that require integer immediate operands to be
x86_64_hilo_int_operand, so that each part is a valid word mode immediate
constant.  As an exception to this rule, doubleword patterns that must be
split before reload, because they require additional scratch registers,
can use take advantage of this ability to create new pseudos, to accept
any immediate constant, and call force_reg on the high and/or low parts
if they are not suitable immediate operands in word mode.

The benefit is shown in the new cmpti3.c test case below.

__int128 x;
int foo()
{
    __int128 t = 0x1234567890abcdefLL;
    return x == t;
}

where GCC with -O2 currently generates:

        movabsq $1311768467294899695, %rax
        xorl    %edx, %edx
        xorq    x(%rip), %rax
        xorq    x+8(%rip), %rdx
        orq     %rdx, %rax
        sete    %al
        movzbl  %al, %eax
        ret

but with this patch now generates:

        movabsq $1311768467294899695, %rax
        xorq    x(%rip), %rax
        orq     x+8(%rip), %rax
        sete    %al
        movzbl  %al, %eax
        ret

2022-08-07  Roger Sayle  <roger@nextmovesoftware.com>

gcc/ChangeLog
	* config/i386/i386.md (*cmp<dwi>_doubleword): Change predicate
	for x86_64_hilo_general_operand to general operand.  Call
	force_reg on parts that are not x86_64_immediate_operand.

gcc/testsuite/ChangeLog
	* gcc.target/i386/cmpti1.c: New test case.
	* gcc.target/i386/cmpti2.c: Likewise.
	* gcc.target/i386/cmpti3.c: Likewise.

This patch adds a new warning to -fanalyzer for jumps through NULL
function pointers.

gcc/analyzer/ChangeLog:
	PR analyzer/105947
	* analyzer.opt (Wanalyzer-jump-through-null): New option.
	* engine.cc (class jump_through_null): New.
	(exploded_graph::process_node): Complain about jumps through NULL
	function pointers.

gcc/ChangeLog:
	PR analyzer/105947
	* doc/invoke.texi: Add -Wanalyzer-jump-through-null.

gcc/testsuite/ChangeLog:
	PR analyzer/105947
	* gcc.dg/analyzer/function-ptr-5.c: New test.

Signed-off-by: David Malcolm <dmalcolm@redhat.com>

This patch to the middle-end's RTL expansion reorders the code in
emit_store_flag_1 so that the backend has more control over how best
to expand/split double word equality/inequality comparisons against
zero or minus one.  With the current implementation, the middle-end
always decides to lower this idiom during RTL expansion using SUBREGs
and word mode instructions, without ever consulting the backend's
machine description.  Hence on x86_64, a TImode comparison against zero
is always expanded as:

(parallel [
  (set (reg:DI 91)
       (ior:DI (subreg:DI (reg:TI 88) 0)
               (subreg:DI (reg:TI 88) 8)))
  (clobber (reg:CC 17 flags))])
(set (reg:CCZ 17 flags)
     (compare:CCZ (reg:DI 91)
                  (const_int 0 [0])))

This patch, which makes no changes to the code itself, simply reorders
the clauses in emit_store_flag_1 so that the middle-end first attempts
expansion using the target's doubleword mode cstore optab/expander,
and only if this fails, falls back to lowering to word mode operations.
On x86_64, this allows the expander to produce:

(set (reg:CCZ 17 flags)
     (compare:CCZ (reg:TI 88)
                  (const_int 0 [0])))

which is a candidate for scalar-to-vector transformations (and
combine simplifications etc.).  On targets that don't define a cstore
pattern for doubleword integer modes, there should be no change in
behaviour.  For those that do, the current behaviour can be restored
(if desired) by restricting the expander/insn to not apply when the
comparison is EQ or NE, and operand[2] is either const0_rtx or
constm1_rtx.

This change just keeps RTL expansion more consistent (in philosophy).
For other doubleword comparisons, such as with operators LT and GT,
or with constants other than zero or -1, the wishes of the backend
are respected, and only if the optab expansion fails are the default
fall-back implementations using narrower integer mode operations
(and conditional jumps) used.

2022-08-05  Roger Sayle  <roger@nextmovesoftware.com>

gcc/ChangeLog
	* expmed.cc (emit_store_flag_1): Move code to expand double word
	equality and inequality against zero or -1, using word operations,
	to after trying to use the backend's cstore<mode>4 optab/expander.

libstdc++-v3/ChangeLog:

	* include/experimental/scope (__cpp_lib_experimental_scope):
	Define.
	* testsuite/experimental/scopeguard/uniqueres.cc: Check macro.

libstdc++-v3/ChangeLog:

	* include/Makefile.am: Add new header.
	* include/Makefile.in: Regenerate.
	* include/experimental/scope: New file.
	* testsuite/experimental/scopeguard/uniqueres.cc: New test.
	* testsuite/experimental/scopeguard/exit.cc: New test.

This excludes value_replacement and store_elim from diamonds as they don't
handle the form properly.

gcc/ChangeLog:

	PR middle-end/106534
	* tree-ssa-phiopt.cc (tree_ssa_phiopt_worker): Guard the
	value_replacement and store_elim from diamonds.

This fixes odd SUCCEEDED dumps from the backthreader registry that
can happen even though register_jump_thread cancelled the thread
as invalid.

	* tree-ssa-threadbackward.cc (back_threader::maybe_register_path):
	Check whether the registry register_path rejected the path.
	(back_threader_registry::register_path): Return whether
	register_jump_thread succeeded.

An unsupported_range temporary is instantiated in every Value_Range
for completeness sake and should be mostly a NOP.  However, it's
showing up in the callgrind stats, because it's not inline.  This
fixes the oversight.

	PR tree-optimization/106514

gcc/ChangeLog:

	* value-range.cc (unsupported_range::unsupported_range): Move...
	* value-range.h (unsupported_range::unsupported_range): ...here.
	(unsupported_range::set_undefined): New.

Loop distribution currently gives up if the outer loop of a loop
nest it analyzes contains a stmt with side-effects instead of
continuing to analyze the innermost loop.  The following fixes that
by continuing anyway.

	PR tree-optimization/106533
	* tree-loop-distribution.cc (loop_distribution::execute): Continue
	analyzing the inner loops when find_seed_stmts_for_distribution
	fails.

	* gcc.dg/tree-ssa/ldist-39.c: New testcase.

Set the return value to 0 when modulo is supported, and to 1 when not supported.

gcc/testsuite/
	* lib/target-supports.exp (check_p9modulo_hw_available): Correct return
	value.

The problem here was a disconnect between splittable_const_int_operand
predicate and the function riscv_build_integer_1 for 32bits with zbs enabled.
The splittable_const_int_operand predicate had a check for TARGET_64BIT which
was not needed so this patch removed it.

Committed as obvious after a build for risc32-elf configured with --with-arch=rv32imac_zba_zbb_zbc_zbs.

Thanks,
Andrew Pinski

gcc/ChangeLog:

	* config/riscv/predicates.md (splittable_const_int_operand):
	Remove the check for TARGET_64BIT for single bit const values.

ChangeLog:

	* MAINTAINERS: Add myself as AutoFDO maintainer.

The P2499R0 paper was recently approved for C++23.

libstdc++-v3/ChangeLog:

	* include/std/string_view (basic_string_view(Range&&)): Add
	explicit as per P2499R0.
	* testsuite/21_strings/basic_string_view/cons/char/range_c++20.cc:
	Adjust implicit conversions. Check implicit conversions fail.
	* testsuite/21_strings/basic_string_view/cons/wchar_t/range_c++20.cc:
	Likewise.

This library defect was recently approved for C++23.

libstdc++-v3/ChangeLog:

	* include/bits/fs_dir.h (directory_iterator): Add comparison
	with std::default_sentinel_t. Remove redundant operator!= for
	C++20.
	* (recursive_directory_iterator): Likewise.
	* include/bits/iterator_concepts.h [!__cpp_lib_concepts]
	(default_sentinel_t, default_sentinel): Define even if concepts
	are not supported.
	* include/bits/regex.h (regex_iterator): Add comparison with
	std::default_sentinel_t. Remove redundant operator!= for C++20.
	(regex_token_iterator): Likewise.
	(regex_token_iterator::_M_end_of_seq()): Add noexcept.
	* testsuite/27_io/filesystem/iterators/lwg3719.cc: New test.
	* testsuite/28_regex/iterators/regex_iterator/lwg3719.cc:
	New test.
	* testsuite/28_regex/iterators/regex_token_iterator/lwg3719.cc:
	New test.

compute_ranges_in_block loops over the import list and then checks the
same bit in exports.  It is nmore efficent to loop over the intersection
of the 2 bitmaps.

	PR tree-optimization/106514
	* gimple-range-path.cc (path_range_query::compute_ranges_in_block):
	Use EXECUTE_IF_AND_IN_BITMAP to loop over 2 bitmaps.

This adds a match.pd rule that drops the bitwwise nots when both arguments to a
subtract is inverted. i.e. for:

float g(float a, float b)
{
  return ~(int)a - ~(int)b;
}

we instead generate

float g(float a, float b)
{
  return (int)b - (int)a;
}

We already do a limited version of this from the fold_binary fold functions but
this makes a more general version in match.pd that applies more often.

gcc/ChangeLog:

	* match.pd: New bit_not rule.

gcc/testsuite/ChangeLog:

	* gcc.dg/subnot.c: New test.

For the diamond PHI form in tree_ssa_phiopt_worker we need to
extract edge e2 sooner.  This changes it so we extract it at the
same time we determine we have a diamond shape.

gcc/ChangeLog:

	PR middle-end/106519
	* tree-ssa-phiopt.cc (tree_ssa_phiopt_worker): Check final phi edge for
	diamond shapes.

gcc/testsuite/ChangeLog:

	PR middle-end/106519
	* gcc.dg/pr106519.c: New test.

This patch adds a new optimization to match.pd. The pattern, -x & 1,
now gets simplified to x & 1, reducing the number of instructions
produced.

This patch also adds tests for the optimization rule.

Bootstrapped/regtested on x86_64-pc-linux-gnu.

	PR tree-optimization/106243

gcc/ChangeLog:

	* match.pd (-x & 1): New simplification.

gcc/testsuite/ChangeLog:

	* gcc.dg/pr106243-1.c: New test.
	* gcc.dg/pr106243.c: New test.

The LC SSA rewrite performs SSA verification at start but the VN
run performed on the unrolled-and-jammed body can leave us with
invalid SSA form until CFG cleanup is run.  So make sure we do that
before rewriting into LC SSA.

	PR tree-optimization/106521
	* gimple-loop-jam.cc (tree_loop_unroll_and_jam): Perform
	CFG cleanup manually before rewriting into LC SSA.

	* gcc.dg/torture/pr106521.c: New testcase.

I've tried to understand how the greedy search works seeing the
bitmap dances and the split into resolve_phi.  I've summarized
the intent of the algorithm as

      // For further greedy searching we want to remove interesting
      // names defined in BB but add ones on the PHI edges for the
      // respective edges.

but the implementation differs in detail.  In particular when
there is more than one interesting PHI in BB it seems to only consider
the first for translating defs across edges.  It also only applies
the loop crossing restriction when there is an interesting PHI.

The following preserves the loop crossing restriction to the case
of interesting PHIs but merges resolve_phi back, changing interesting
as outlined with the intent above.  It should get more threading
cases when there are multiple interesting PHI defs in a block.
It might be a bit faster due to less bitmap operations but in the
end the main intent was to make what happens more obvious.

	* tree-ssa-threadbackward.cc (populate_worklist): Remove.
	(back_threader::resolve_phi): Likewise.
	(back_threader::find_paths_to_names): Rewrite greedy search.

The P2549R1 paper was accepted for C++23. I already implemented it for
our <expected>, but I didn't rename the private daata members, only the
public member functions. This renames the data members for consistency
with the working draft.

libstdc++-v3/ChangeLog:

	* include/std/expected (unexpected::_M_val): Rename to _M_unex.
	(bad_expected_access::_M_val): Likewise.

My P2467R1 proposal was accepted for C++23 so there's an official value
for this macro now.

libstdc++-v3/ChangeLog:

	* include/bits/ios_base.h (__cpp_lib_ios_noreplace): Update
	value to 202207L.
	* include/std/version (__cpp_lib_ios_noreplace): Likewise.
	* testsuite/27_io/basic_ofstream/open/char/noreplace.cc: Check
	for new value.
	* testsuite/27_io/basic_ofstream/open/wchar_t/noreplace.cc:
	Likewise.

When using a mutex and condition variable, the notifying thread needs to
increment _M_ver while holding the mutex lock, and the waiting thread
needs to re-check after locking the mutex. This avoids a missed
notification as described in the PR.

By moving the increment of _M_ver to the base _M_notify we can make the
use of the mutex local to the use of the condition variable, and
simplify the code a little. We can use a relaxed store because the mutex
already provides sequential consistency. Also we don't need to check
whether __addr == &_M_ver because we know that's always true for
platforms that use a condition variable, and so we also know that we
always need to use notify_all() not notify_one().

Reviewed-by: Thomas Rodgers <trodgers@redhat.com>

libstdc++-v3/ChangeLog:

	PR libstdc++/106183
	* include/bits/atomic_wait.h (__waiter_pool_base::_M_notify):
	Move increment of _M_ver here.
	[!_GLIBCXX_HAVE_PLATFORM_WAIT]: Lock mutex around increment.
	Use relaxed memory order and always notify all waiters.
	(__waiter_base::_M_do_wait) [!_GLIBCXX_HAVE_PLATFORM_WAIT]:
	Check value again after locking mutex.
	(__waiter_base::_M_notify): Remove increment of _M_ver.

The tuple pretty printer uses 1-based indeces which is quite confusing
considering the access to the same values with the std::get functions
uses 0-based indeces.  This patch changes the pretty printer since
this is not a guaranteed API.

libstdc++-v3/ChangeLog:

	* python/libstdcxx/v6/printers.py (class StdTuplePrinter): Use
	zero-based indeces just like std:get takes.

dg.exp=pr104612.c fails with an ICE on s390x, because copysignv2sf3
produces an insn that vsel<mode> is supposed to recognize, but can't,
because it's not defined for V2SF.  Fix by defining it for all vector
modes supported by copysign<mode>3.

gcc/ChangeLog:

	* config/s390/vector.md (V_HW_FT): New iterator.
	* config/s390/vx-builtins.md (vsel<mode>): Use V_HW_FT instead
	of V_HW.

Testing has shown that using the load vector pair and store vector pair
instructions for block moves has some performance issues on power10.

A patch on June 11th modified the code so that GCC would not set
-mblock-ops-vector-pair by default if we are tuning for power10, but it would
set the option if we were tuning for a different machine and have load and store
vector pair instructions enabled.

This patch eliminates the code setting -mblock-ops-vector-pair.  If you want to
generate load vector pair and store vector pair instructions for block moves,
you must use -mblock-ops-vector-pair.

2022-08-03   Michael Meissner  <meissner@linux.ibm.com>

gcc/

	* config/rs6000/rs6000.cc (rs6000_option_override_internal): Remove code
	setting -mblock-ops-vector-pair.

When killing a def in the path ranger, there is no need to walk the set
of existing equivalences clearing bits.  An equivalence match requires
that both ssa-names have to be in each others set.  As killing_def
creates a new empty set contianing only the current def,  it already
ensures false equivaelnces won't happen.

	PR tree-optimization/106514
	* value-relation.cc (path_oracle::killing_def) Do not walk the
	  equivalence set clearing bits.

The regexps in hte test btf-int-1.c were not working properly with the
commenting style of at least one target: powerpc64le-linux-gnu.  This
patch changes the test to use better regexps.

Tested in bpf-unkonwn-none, x86_64-linux-gnu and powerpc64le-linux-gnu.
Pushed to master as obvious.

gcc/testsuite/ChangeLog:

	PR testsuite/106515
	* gcc.dg/debug/btf/btf-int-1.c: Fix regexps in
	scan-assembler-times.

This patch adds support for three-way min/max recognition in phi-opts.

Concretely for e.g.

#include <stdint.h>

uint8_t three_min (uint8_t xc, uint8_t xm, uint8_t xy) {
	uint8_t	 xk;
    if (xc < xm) {
        xk = (uint8_t) (xc < xy ? xc : xy);
    } else {
        xk = (uint8_t) (xm < xy ? xm : xy);
    }
    return xk;
}

we generate:

  <bb 2> [local count: 1073741824]:
  _5 = MIN_EXPR <xc_1(D), xy_3(D)>;
  _7 = MIN_EXPR <xm_2(D), _5>;
  return _7;

instead of

  <bb 2>:
  if (xc_2(D) < xm_3(D))
    goto <bb 3>;
  else
    goto <bb 4>;

  <bb 3>:
  xk_5 = MIN_EXPR <xc_2(D), xy_4(D)>;
  goto <bb 5>;

  <bb 4>:
  xk_6 = MIN_EXPR <xm_3(D), xy_4(D)>;

  <bb 5>:
  # xk_1 = PHI <xk_5(3), xk_6(4)>
  return xk_1;

The same function also immediately deals with turning a minimization problem
into a maximization one if the results are inverted.  We do this here since
doing it in match.pd would end up changing the shape of the BBs and adding
additional instructions which would prevent various optimizations from working.

gcc/ChangeLog:

	* tree-ssa-phiopt.cc (minmax_replacement): Optionally search for the phi
	sequence of a three-way conditional.
	(replace_phi_edge_with_variable): Support diamonds.
	(tree_ssa_phiopt_worker): Detect diamond phi structure for three-way
	min/max.
	(strip_bit_not, invert_minmax_code): New.

gcc/testsuite/ChangeLog:

	* gcc.dg/tree-ssa/split-path-1.c: Disable phi-opts so we don't optimize
	code away.
	* gcc.dg/tree-ssa/minmax-10.c: New test.
	* gcc.dg/tree-ssa/minmax-11.c: New test.
	* gcc.dg/tree-ssa/minmax-12.c: New test.
	* gcc.dg/tree-ssa/minmax-13.c: New test.
	* gcc.dg/tree-ssa/minmax-14.c: New test.
	* gcc.dg/tree-ssa/minmax-15.c: New test.
	* gcc.dg/tree-ssa/minmax-16.c: New test.
	* gcc.dg/tree-ssa/minmax-3.c: New test.
	* gcc.dg/tree-ssa/minmax-4.c: New test.
	* gcc.dg/tree-ssa/minmax-5.c: New test.
	* gcc.dg/tree-ssa/minmax-6.c: New test.
	* gcc.dg/tree-ssa/minmax-7.c: New test.
	* gcc.dg/tree-ssa/minmax-8.c: New test.
	* gcc.dg/tree-ssa/minmax-9.c: New test.

In upstream dmd, the compiler front-end and run-time have been merged
together into one repository.  Both dmd and libdruntime now track that.

D front-end changes:

    - Deprecated `scope(failure)' blocks that contain `return' statements.
    - Deprecated using integers for `version' or `debug' conditions.
    - Deprecated returning a discarded void value from a function.
    - `new' can now allocate an associative array.

D runtime changes:

    - Added avx512f detection to core.cpuid module.

Phobos changes:

    - Changed std.experimental.logger.core.sharedLog to return
      shared(Logger).

gcc/d/ChangeLog:

	* dmd/MERGE: Merge upstream dmd d7772a2369.
	* dmd/VERSION: Bump version to v2.100.1.
	* d-codegen.cc (get_frameinfo): Check whether decision to generate
	closure changed since semantic finished.
	* d-lang.cc (d_handle_option): Remove handling of -fdebug=level and
	-fversion=level.
	* decl.cc (DeclVisitor::visit (VarDeclaration *)): Generate evaluation
	of noreturn variable initializers before throw.
	* expr.cc (ExprVisitor::visit (AssignExp *)): Don't generate
	assignment for noreturn types, only evaluate for side effects.
	* lang.opt (fdebug=): Undocument -fdebug=level.
	(fversion=): Undocument -fversion=level.

libphobos/ChangeLog:

	* configure: Regenerate.
	* configure.ac (libtool_VERSION): Update to 4:0:0.
	* libdruntime/MERGE: Merge upstream druntime d7772a2369.
	* libdruntime/Makefile.am (DRUNTIME_DSOURCES): Add
	core/internal/array/duplication.d.
	* libdruntime/Makefile.in: Regenerate.
	* src/MERGE: Merge upstream phobos 5748ca43f.
	* testsuite/libphobos.gc/nocollect.d:

A SET operation that writes memory may have the same value as an
earlier store but if the alias sets of the new and earlier store do
not conflict then the set is not truly redundant.  This can happen,
for example, if objects of different types share a stack slot.

To fix this we define a new function in cselib that first checks for
equality and if that is successful then finds the earlier store in the
value history and checks the alias sets.

The routine is used in two places elsewhere in the compiler:
cfgcleanup and postreload.

gcc/ChangeLog:

	PR rtl-optimization/106187
	* alias.h (mems_same_for_tbaa_p): Declare.
	* alias.cc (mems_same_for_tbaa_p): New function.
	* dse.cc (record_store): Use it instead of open-coding
	alias check.
	* cselib.h (cselib_redundant_set_p): Declare.
	* cselib.cc: Include alias.h
	(cselib_redundant_set_p): New function.
	* cfgcleanup.cc: (mark_effect): Use cselib_redundant_set_p instead
	of rtx_equal_for_cselib_p.
	* postreload.cc (reload_cse_simplify): Use cselib_redundant_set_p.
	(reload_cse_noop_set_p): Delete.

The option prints TOP N counters in a stable format
usage for comparison (diff).

gcc/ChangeLog:

	* doc/gcov-dump.texi: Document the new option.
	* gcov-dump.cc (main): Parse the new option.
	(print_usage): Show the option.
	(tag_counters): Sort key:value pairs of TOP N counter.

gcc/ChangeLog:

	* profile.cc (compute_branch_probabilities): Do not collect
	stats unless TDF_DETAILS.